EUV light source and apparatus for EUV lithography

Abstract

A metal reuse system for an extreme ultra violet (EUV) radiation source apparatus includes a first metal collector for collecting metal from vanes of the EUV radiation source apparatus, a first metal storage coupled to the first metal collector via a first conduit, a metal droplet generator coupled to the first metal storage via a second conduit, and a first metal filtration device disposed on either one of the first conduit and the second conduit.

What is claimed is: 
     
       1. A metal reuse system for an extreme ultra violet (EUV) radiation source apparatus, comprising:
 a first metal collector for collecting metal from vanes of the EUV radiation source apparatus; 
 a first metal storage coupled to the first metal collector via a first conduit; 
 a metal droplet generator coupled to the first metal storage via a second conduit; and 
 a first metal filtration device disposed on either one of the first conduit and the second conduit. 
 
     
     
       2. The metal reuse system of  claim 1 , wherein the metal is tin or tin doped with one of Ga and In. 
     
     
       3. The metal reuse system of  claim 2 , wherein the first metal collector is a heated tin vane bucket. 
     
     
       4. The metal reuse system of  claim 2 , further comprising a second metal filtration device,
 wherein the first metal filtration device is disposed on the first conduit and the second metal filtration device is disposed on the second conduit. 
 
     
     
       5. The metal reuse system of  claim 2 , further comprising:
 a first pressurizing device coupled to the first metal storage via a third conduit; 
 a first valve disposed on the first conduit; 
 a second valve disposed on the second conduit; 
 a third valve disposed on the third conduit; and 
 a controller that controls the first pressurizing device, the first valve, the second valve and the third valve. 
 
     
     
       6. The metal reuse system of  claim 5 , wherein the controller is configured to:
 close the second and third valves and open the first valve when an amount of metal in the metal droplet generator is more than a threshold amount, and 
 supply the metal stored in the first metal storage by operating the first pressurizing device and opening the second valve and the third valve and closing the first valve, when the amount of the metal in the metal droplet generator becomes equal to or less than the threshold amount. 
 
     
     
       7. The metal reuse system of  claim 5 , wherein the first to third conduits are heated at a temperature higher than a melting point of the metal. 
     
     
       8. The metal reuse system of  claim 5 , further comprising:
 a second metal collector for collecting metal droplets generated from the metal droplet generator, which are not irradiated by laser; 
 a second metal storage coupled to the second metal collector via a fourth conduit; 
 a fifth conduit connecting the metal droplet generator and the second metal storage; and 
 a second metal filtration device disposed on either one of the fourth conduit and the fifth conduit. 
 
     
     
       9. The metal reuse system of  claim 8 , further comprising:
 a second pressurizing device coupled to the second metal storage via a sixth conduit; 
 a fourth valve disposed on the fourth conduit; 
 a fifth valve disposed on the fifth conduit; and 
 a sixth valve disposed on the sixth conduit, 
 wherein the controller is configured to control the second pressurizing device, the fourth valve, the fifth valve and the sixth valve. 
 
     
     
       10. A metal reuse system for an extreme ultra violet (EUV) radiation source apparatus, comprising:
 a first metal collector for collecting tin from vanes of the EUV radiation source apparatus; 
 a second metal collector for collecting metal droplets generated from a metal droplet generator, which are not irradiated by laser; 
 a first conduit extending from the first metal collector; 
 a second conduit extending from the second metal collector; 
 a third conduit coupled to the first conduit and the second conduit; 
 a metal storage coupled to the third conduit and coupled to the metal droplet generator via a fourth conduit; and 
 one or more metal filtration devices disposed on one of the first, second, third and fourth conduits. 
 
     
     
       11. The metal reuse system of  claim 10 , wherein the metal is tin or tin doped with at least one of In and Ga. 
     
     
       12. The metal reuse system of  claim 11 , wherein the first metal collector is a heated tin vane bucket (HTVB) and the second metal collector is a tin droplet collector. 
     
     
       13. The metal reuse system of  claim 11 , wherein one metal filtration devices is disposed on the first conduit and another metal filtration device is disposed on the second conduit. 
     
     
       14. The metal reuse system of  claim 10 , further comprising:
 a pressurizing device coupled to the metal storage via a fifth conduit; 
 a first valve disposed on the third conduit; 
 a second valve disposed on the fourth conduit; 
 a third valve disposed on the fifth conduit; and 
 a controller that controls the pressurizing device, the first valve, the second valve and the third valve. 
 
     
     
       15. The metal reuse system of  claim 14 , wherein the controller is configured to:
 close the second and third valves and open the first valve when an amount of metal in the metal droplet generator is more than a threshold amount, and 
 supply metal stored in the metal storage by operating the pressurizing device and opening the second valve and the third valve and closing the first valve, when the amount of metal in the metal droplet generator becomes equal to or less than the threshold amount. 
 
     
     
       16. An extreme ultra violet (EUV) radiation source apparatus, comprising:
 a collector; 
 a target droplet generator for generating a metal droplet; 
 a rotatable debris collection device including vanes; 
 a first metal reuse system; and 
 a chamber enclosing at least the collector and the rotatable debris collection device, wherein: 
 the first metal reuse system includes:
 a first metal collector for collecting metal from vanes of the EUV radiation source; 
 a first metal storage coupled to the first metal collector via a first conduit; 
 a second conduit connected to the metal droplet generator and the first metal storage; and 
 a first metal filtration device disposed on either one of the first conduit and the second conduit. 
 
 
     
     
       17. The EUV radiation source of  claim 16 , wherein:
 the first metal reuse system further includes a second metal filtration device, and 
 the first metal filtration device is disposed on the first conduit and the second metal filtration device is disposed on the second conduit. 
 
     
     
       18. The EUV radiation source of  claim 16 , wherein:
 the first metal reuse system further includes:
 a first pressurizing device coupled to the first metal storage via a third conduit; 
 a first valve disposed on the first conduit; 
 a second valve disposed on the second conduit; 
 a third valve disposed on the third conduit; and 
 a controller that controls the first pressurizing device, the first valve, the second valve and the third valve. 
 
 
     
     
       19. The EUV radiation source of  claim 18 , wherein the controller is configured to:
 close the second and third valves and open the first valve when an amount of metal in the metal droplet generator is more than a threshold amount, and 
 supply metal stored in the first metal storage by operating the first pressurizing device and opening the second valve and the third valve and closing the first valve, when the amount of metal in the metal droplet generator becomes equal to or less than the threshold amount. 
 
     
     
       20. The EUV radiation source of  claim 16 , further comprising a second metal reuse system including:
 a second metal collector for collecting metal droplets generated from the metal droplet generator, which are not irradiated by laser; and 
 one or more conduit coupled between the second metal collector and the metal droplet generator.